Stop mechanism



Marc-h 12, 1935..

J. H. SAYRES STOP MECHANISM Filed June 16, 1934 2 Sheets-Shee t 1 INVENTOR JOHN H. SAYRES BY HIS ATTORNEYS March 12, 1935. J. H. SAYRES STOP MECHANISM 2 Sheets-Sheet 2 Filed June 16, 1934 m wm & mm mm INVENTOR JOHN H. SAYRES BY HIS ATTORNEYS Patented Mar. 12, 1935 UNITED STATES PATENT OFFICE.

r 1 1 1,994,405 r A v STOP MECHANISM John H. 'Sa yres Chappaqua, N. Y. A plication June 16, 1934, Serial No. 730,988

19 Claims.

This invention relates to stop mechanisms .of

the type disclosed in my prior Patent No. 1,-

628,474 granted May 10th, 192?, and has for its principal object to simplify and'improve and 5 reduce the cost of manufacture of stop-mocha nisms of this character. As distinguished from the toggle mechanism of my prior :patent, the

present invention employs a lever having unequal lever arms.

:Other objects will become apparent :as the following description proceeds, as read in .con-

of the stop mechanism with the cover broken away;

Figure 15 is a vertical section taken along the line 5-5 of Figure 4;

Figure :6 is an end elevation of the retaining member for the modification; and

Figure 7 is a side elevation of the same.

The stop mechanism comprises .an .actuator 10, which may be connected in any known manner-to :the machine .or instrument-aility to be stopped thereby, for any nf the purposes set forth in my prior patent, and is urged in :one direction by a spring 11. This actuator has an abutment 12, which :in the preferred embodiment shown, comprises the end of a notch cutinto the actuator 10.

.A retaining member 13 is provided for ,holding the actuator .10 against the action of the spring 11. 14, and is provided with an abutment l5 cooperating with the actuator abutment l2 .and'an arm .16 extending laterally from the pivot 114,

and engaged at its free endfby a latch '17.

.In the automatic electric stop mechanism shown, the latch 17 constitutes the armature of an electromagnet 18. The magnet circuit includes one or more pairs of contacts arranged" as shown and described in my prior patent to be closed by the condition which renders actuation of the stop mechanism desirable. A circuit braker 19 is "provided for the magnetcircuit, and 'is arranged to be operated by a moving part of the stop mechanism.

The retaining member has a pivot in operation, closing the contacts energizes the electromagnet 18, which pulls down the latch 17'. This frees the outer end of the arm 16, and the force of the'spring 1'1 transmitted by the actuator 10 and its abutment 12 to abutment 1'5 of the retaining member 13 and turns 5 it with'the arm 16 as a unit about the pivot 14, through an arc of about As the retaining member 13 turns the abutment "15 turns with it, and a fiat portion of the retaining member comes into position par- 10 allel to the actuator 10; As this fiat portion is but a relatively small radial distance from the 'pivot 14, it clears the actuator 10 when it is parallel thereto, thusxreleasing the actuator I forfmovement under the force of the spring 11. 15

When the actuator is returned to reset the stop mechanism, the spring 11 being thereby extended, the spring 22 causes return rotation of the retaining member, as soon as the actuator a-btument 12 passes the retainer abutment 20 15, thus swinging the arm 16 to set position. This return swing of the arm 16 causes the end thereof to engage the cam portion 21 of the latch 17, and depress the same until it rides off the end. The spring 23 then returns the latch to 'set position, in which it remains until the control contacts 'areclosed again. 1

1 In the form shown in Figure 1, the automatic electric stop mechanism is housed in a casing 25. The actuator bar 10 slides through guides 26 formed in bosses in the casing wall. The casing 25 is preferably rectangular, having side walls 28, 29, 30 and 31. The pivot 14 is near the corner thereof formed'by the junction of walls 28 and 29, and has bearings 2'7 in bosses in the front and back of the casing. The actuator 10 is near the bottom *wall28 of the casing, just above the pivot 14. r

The retainer member 13 is shown with a rectangular portion, but it may be of any other. cross-section and provided with an abutment face, and the arm '16 extends at right angles to the rectangular portion; The armature 1'7 is near the top wall 30 and ispivoted at 24 in the corner formed by walls 30 and 31. The magnet 18 is located between the actuator 10 and the latch 1'7, being mounted on an angle clip secured to the back of the casing. The circuit breaker is also mounted on this clip, and 111811- lated therefrom and comprises .a pair of spring contact blades '20 in the magnet circuit and adapted to receive a conductor disk 19 carried by the arm 16 and insulated therefrom.

Thus the arm 16 swings from a position adjacent the wall 29 to a position adjacent the r of the housing.

wall 28, passing in front of the magnet 18, and promptly breaking the circuit therethrough. With this arrangement, the parts are very compact and at the same time, the maximum length of the arm 16 is available for leverage, while the length of the abutment 15 is reduced toa minimum. Also, the engagement of the latch 17 withthe end of the arm 16 is edge to edge, so that a minimum latch movement is required for release. p A

A modified embodiment of the invention "is shown in Figures 4, 5, 6 and 7. Here the actuator is a cable wound on a drum, and a trip deg vice is added to permit more than onerevolution of the drum.

One end of the cable 49 is secured. to the drum 50 which is urged to rotate in one direction by a spiral spring 51. The abutment-52 ofthe actuator is formed by the side of a notch,

cut into the flange of the drum 50. V

The retaining member 53, which holds the actuator against the action ofthespringlil, has

a pivot 54, and an abutment 55 cooperating with the actuator abutment 52. Anarm- 56 extends laterally from the, pivot 54. and is engaged at its free end by alatch 57 preferably formingthearmature of the electromagnet 5 8;.-, ,e circuit 7 of which, as described for the preferred embodiment, includes the control contacts and a circuit breaker 59 arranged to be operated by a moving part of the stop mechanism.

This circuit breaker comprisesanupper con: ductor blade 60 and a lower spring contact blade 61, both mounted on and insulated from-thebase The spring contact blade 61 is.

normally in contact withthe turned down outer end of the upper conductor blade 60.

A trigger 40 is pivoted at 41 near the actuator 50 and the retaining member 53. v This trigger is in theform of a bell crank, the arm 40a, of

which-has a lug 42 adapted to enter .a slot 43 in the retaining member 53. The other arm 44 is faced with insulating material 44;; and operates the circuit breaker;59 by engaging the projecting end of the lower spring contactiolade 61. A spring detent 45 selectively engages notches 46 and 47 to hold the trigger, in its two respective positions. Atrip button 48 is secured to the cable 49, in position to engage the trigger In operation, closing the Qcontacts energizes:

the electromagnet 58, which pulls. down theiatch 5'7. This frees the outer end of the arm 56, and

the force of the spring 51 is transmitted by the actuator 50 and its abutment 52 to abutment 55 of the retaining member 53 and turns it with the arm 56 as a unit about the pivot 54, through an arc of about t a As the retaining member 53 turns the abutment 55 turns with it, and the fiat portion of the retaining member comes into position approximately parallel to a tangent to the circumference of the flange of the drum 50. ,As the flat.por-,

tion is but a relatively small radial distance from the pivot 54, it clears the. drum 5 and its flange, thus releasing the actuator for movement under the force of the spring 51.

-However, the spring 551 winds up the cable 49 on the drum 50, and the button 48 on the cable engages the trigger 40 and moves vit'from thefull line position shownin Figure 4, with-the spring detent '45 engaging the notch 46, to ;the dotted line position in which it gengages-the;

notch 47. Thiscauses the lug 42 to= enter the s ot 8., and athe same t e. a sesthea m;

44 to open the circuit breaker 59, by depressing the blade 61 out of contact with the blade 60.-

The lug 42 holds the retaining member 53 against the action of spring 62, so that the gages the trigger 40 and moves it back to the full line-position, with the notch ,46 engaging around to the retaining member 53, the spring the detent 45. v This movesup the arm 44 and" releases the circuit breaker blade 61, and also i withdraws-the lug 42 from the slot 43, which releases the retaining member 53. Hence, when the notch in the flange of the drum 50 comes 62 rotates it :backto its original position, be-i.

cause the retaining abutment 55 isfree to'enter the: notch ,and engage the aetuatorabutmenti I 52, thus swinging the arm 56 to set position? This return swing of thearm 56 causes the-end thereof. to engage the. cam portion 64 of the latch 57 and depress the same until-it rides iofi;

the end. The spring 63 then returnsthelatch. 57 to set position in'which it remainsuntil the contacts areclosed again. 5

While two embodiments of 1 the invention have been disclosed, the invention is not lime ited to the. details thereof, butinsteadfembraces such modifications of the broad idea .as fall ea,

within the scopejofythe appended claimsmfl 1 .WhatIclaim is:

1. In a stop mechanism comprising; an 'actu-il' ator and means urging said actuator in Ione' direction, the combination of a pivoted retain-j ing member. having a stationary-.qaxis, cooperatin'g abutments on .said retainingmembenand. said actuator, a latch for said retaining member,.-

and means for operating said latch to release I saidretaining member. I

2.. In. a stop mechanism comprising'an ,actuator and mean'srforurging-said actuatorinbnev direction, the. combination 'of a'memberhaving 3 one end pivoted about a stationary axis adjacent 1 to said actuator, latching means engagingthe other end .ofsaidpivoted member and an abut.-' ment on said pivoted member engagingdsaid' actuator...,...

'3. In a stop mechanism comprising'an'actue ator having-an abutment, and means for urging. said actuator in'one direction, the combination i of a pivoted retaining member having an abutfor moving sa'idlatch clear ofrsaid" arm, said retaining member having a portion of lesser radial extent than its abutment. f1 4. In a stop mechanism comprising an actu atorhav'ing an abutment, means tor mounting;

said actuator ,for movementI'o'f said ab'utment in .a predetermined path, and means urging said actuator to'f'cause, movement of said abutment. n s d Pa i 9 6 dir t o ;th i b tion of, a pivoted, retaining :rnember extending, into; said path, an armon said retaining member, a latch engaging vsaidarm, and means for mQYinasaidJat le ai am. sa d r taining member having a flat portionclear of said path whenxparallel thereto. I

5.,Ina stop mechanism comprising anactue ator and-means for urging said actuator in one direction, the combination of a casing having side walls, a member pivoted about a stationary axis in said'casingv to swing from a position adjacent one side wall toa position adjacent the next side wall, means in said casing engaging said member, andan abutment on said member engaging said actuator.

6. In a stop mechanism comprising an actuator and means for urging said actuator in one direction, the combination of a casing having side walls, a member pivoted in said casing adjacent the junction of two of said side walls and adapted to swing from a position adjacent one to a position adjacent the other, means in said casing adjacent a third of said side walls and engaging said member, and an abutment on said member engaging said actuator.

7. In an automatic electric stop mechanism comprising an actuator and means for urging said actuator in one direction, the combination of a casing adapted to receive said actuator, a retaining member pivoted about a stationary axis in said casing and having an abutment engaging said actuator, an arm on said retainng member, a latch engaging said arm, and an electromagnet in said casing for operating said latch, said arm being positioned axially of said retaining member to clear said magnet when released by said latch.

8. In an automatic electric stop mechanism comprising an actuator andmeans for urging said actuator in one direction, the combination of an arm pivoted about a stationary axis at one side of said actuator member, an electromagnet having an armature engaging said arm,

an abutment on said arm engaging said actuator member, a circuit breaker, means for operating said circuit breaker when said arm is released by said armature, and means for automatically resetting the stop mechanism when said actuator is returned.

9. In an automatic electric stop mechanism comprising an actuator having an abutment, means for mounting said actuator for movement of said abutment in a predetermined path, and means urging said actuator to cause movement of said abutment along said path in one direction, the combination of a pivoted retaining member having an abutment extending into said path and cooperating with said actuator abutment to retain'said actuator against the action of said urging means, an arm movable with said retaining member about its pivot, a latch engaging said arm, and an electromagnet for moving said latch clear of said arm, said retaining member having a portion of lesser'radius than its abutment, whereby when said latch is released by said electromagnet, said urging means causes said actuator abutment to move said retaining member abutment and arm aboutsaid pivot, and bring said portion of lesser radius into position opposite said path, thereby permitting said actuator abutment to pass said retaining member.

10. In a stop mechanism, in combination, a pivoted actuator, means urging rotation of said actuator about its pivot in one direction, a pivoted retaining member having a stationary axis, cooperating abutments on said retaining member and said actuator member, an element rigid with said retaining member, a latch engaging saidelement and means for moving said latch clear of said element. 1

11. In a stop mechanism, in actuator comprising .a: drum having a a cable wound thereon, means for urging said drum to rotate in: one direction, an arm pivoted about a stationary axis adjacent one end 'at one side of said drum, latching meansiengaging' the-other end of said ar and an abutment on said. arm

engaging said drum.

12. In a? stop mechanism, .in combination, a rotary actuator, means for urgingrotation of said actuator in one direction, a pivoted retaining member having a stationary axis, cooperating abutments on said retaining member and said actuator for preventing said rotation, an element rigid with said retaining member, a latch engaging said element, means for moving said latch clear of said element, and means for holding said retaining member abutment clear of said actuator abutment for more than one revolution of said actuator.

13. In a stop mechanism, in combination, an actuator, means for urging said actuator in one direction, a pivoted retainingimember having a stationary axis, cooperating abutments on said retaining member and said actuator, an element rigid with said retaining member, a latch engaging said element, means for'moving said latch clear of said element whereby said urging means causes said abutments to move said retaining member about its pivot, and means for holding said retaining member in its second position. 1

14. In a stop mechanism comprising an actuator and means for urging said actuator in one direction, the combination of a pivoted arm having a stationary axis, an electromagnet having an armature engaging said arm, an abutment rigid with said arm and engaging said actuator, a circuit breaker, and means for operating said circuit breaker when said arm is released by said armature and for holding said arm in released position.

15. In a stop mechanism comprising an actuator having an abutment, means urging said actuator to cause movement of said abutment in an arcuate path, the combination of a pivoted retaining member having an abutment extending into said path, an arm movable with said retaining member about its pivot, a latch engaging said arm, means for releasing said latch, said retaining member having a portion of lesser radius than its abutment whereby when said latch is released, said urging means causes said actuator abutment to move said retaining member to bring said portion of lesser radius into position opposite said path, and means for holding said retaining member in said position to permit said actuator abutment to repeatedly pass said retaining member.

16. In a stop mechanism comprising an actuator and means urging said actuator in one direction, the combination of a pivoted retaining member having a stationary axis, cooperat= ing abutments on said retaining member and said actuator, a latch for said retaining member, means for releasing said latch and means for resetting said retaining member and latch upon restoring said actuator to position for engage- 'ment by the retaining member.

17. In a stop mechanism comprising an actuator and means urging said actuator in one direction, the combination of a pivoted retaining member having a stationaryaxis, cooperating combination ,an

for holding said stop means disengaged from said actuator.

19. In a stop mechanism, comprising-anactm. ator and means for urging said actuatorin one" direction, the combination of stop means pivoted about a stationary axis forpreventingmovement I of said actuator by said urging means, means for disengaging and. holding said stop means disengaged from said actuator and means for resetting said. stop actuator.

means upon restoring said JOHN H. sAYREs. 10 

